Winder with constant distance between package and guide roll



Nov. 14, 1961 R L. AKERS 3,008,653

WINDER WITH CONSTANT DISTANCE BETWEEN PACKAGE AND GUIDE ROLL Filed Feb. 15, 1960 3 ShQQtS-ShGGt l INVENTOR RICHARD L. AKERS BY MW ATTORNEY Nov. 14, 1961 R. L. AKERS 3,

WINDER .WITH CONSTANT DISTANCE BETWEEN PACKAGE AND GUIDE ROLL Filed Feb. 15, 1960 5 Sheets-Sheet 2 INVENTOR RICHARD L. AKERS ATTORNEY Nov. 14, 1961 R. AKERS 3,008,658

I WINDER WITH CONSTANT DISTANCE BETWEEN PACKAGE AND GUIDE ROLL I Filed Feb. 15, 1960 5 Sheets-Sheet 3 FIGJJI INVENTOR RICHARD L. AKERS ATTORNEY United States Patent ,0

3,008,658 WINDER WITH CONSTANT DISTANCE BETWEEN PACKAGE AND GUIDE ROLL Richard L. Akers, Claymont, Del., assignor to E. I. du Pont de Nemours and Company, Wilmington, Del., a corporation of Delaware Filed Feb. 15, 1960, Ser. No. 8,642 5 Claims. (Cl. 242-18) This invention relates to an apparatus for winding filamentous materials such as threads, yarns, strands, and the like and more particularly to a surface driven roll apparatus for the high speed cross winding of synthetic textile fibers.

STATEMENT OF THE ART Windups employing a surface drive are common in the art. These permit operating the drive roll at a constant rotational speed while maintaining a constant surface velocity of the driven package despite the growth of the package as the filamentous material is wound thereon. Auxiliary means are commonly employed to traverse the material upon the winding package. These means ordinarily comprise either a grooved traversing roll or a cam actuated reciprocating traverse guide, the cam having a guide engaging groove generally helical in nature and either with or without crossovers. Equipment of this type is widely used and serves adequately at low and moderate speeds. It is ordinarily limited to speeds well below 2,000 yards per minute.

OBJECTS The object of the present invention is to provide a novel and useful apparatus for the high speed cross winding of filamentous materials.

Another object is to provide a compact apparatus for the high speed cross winding of filamentous material which maintains a low uncontrolled yarn length at a relatively constant break angle.

A further object is to provide an appartus for cross winding filamentous materials at speeds of from about 3,000 to about 4,000 yards per minute.

Other objects will become apparent in the course of the following specification and claims.

STATEMENT OF INVENTION In accordance with the present invention apparatus for the high speed winding of filamentous material using a surface drive is provided wherein the growing yarn package and the drive roll are simultaneously moved in spaced relation to a traverse mechanism fixed to the machine frame, the spaced relationship being so controlled that a substantially minimum uncontrolled yarn length is obtained at all stages of package growth with little change in the yarn break angle and with a substantially minimum operable clearance between the yarn guide of the traverse cam follower and the windup body.

DRAWINGS The invention will be more readily understood by reference to the drawings.

FIGURE I is a schematic diagram illustrating the concept of yarn break angle.

FIGURE II is a schematic diagram illustrating the concept of uncontrolled yarn length and comparing the theoretically correct path of the yarn bundle to accomplish the purposes of the present invention with the practical path provided by the structure of the present invention.

FIGURE III is a schematic diagram illustrating the relative motion of a surface drive roll for a windup roll and the yarn bundle thereof, the said windup roll and yarn bundle following the related paths provided for them by the apparatus of the present invention.

FIGURE IV is a schematic illustration of the apparatus of the present invention, the windup roll being empty.

FIGURE V is a schematic illustration of the apparatus of the present inventionwherein the windup roll contains a full yarn package.

FIGURE VI is a series of curves for a typical package preparation on an apparatus of the present invention wherein package diameter is plotted asabscissa against uncontrolled yarn length (curve a) and break angle (curve b) as ordinate. Curve 0 shown in the dotted line describes the break angle deviation for'an alternative motion.

DETAILED DECRIPTION Referring particularly to FIGURE I, yarn 1 passes through yarn guide 2 of traverse cam follower (not shown) onto a windup body 3, passing from yarn guide 2 to the point ofyarn line contact 5 with the 'windup body the yarn sweeps'out a break angle 6 from zero break angle line 4 (i.e., the yarn path when the windup body is tangent to a stretched yarn line passing through yarn guide 2). It will be obvious from a consideration of the figure that a clearance c must be maintained between yarn guide 2 and windup body 3. The yarn length extending from the yarn guide 2 to point of contact '5 shown on the drawing as y is designated hereinafter uncontrolled yarn length. As y increases the apparatus has a tendency to overthrow ends and to produce non-straight package edges and improperly formed package surfaces. In par ticular, where the rate of reversal of the traverse mechanism is slow and the uncontrolled yarn length is relatively large, the edges of the packages which are formed at reversal usually undergo considerable build up causing the periphery of the package to have a saddle-shaped ap-' pearance, which because of its hard and raised edges does not handle properly in textile processing. A relatively minor, steady increase in y during windup have been observed to improve the stability of the yarn package however since it produces tapered edges with the largest package length at the core. Since goodpackage construction when yarn'is wound using a surface drive at high speeds requires that the uncontrolled yarn length y be maintained at minimum, it is important to maintain clearance c at a minimum consonant with safe operation. To keep, the length small, the traverse must be placed close to the winding package but may not rub the surface. In the practical case, if such a small and constant unsupported to a considerable diameter, there will be interference between the traverse mechanism and the package because the mechanism extends beyond the 'yarn line. Control of break angle 6 within limits and maintaining its variations at a minimum is important to avoid yarn degradation. If the angle is excessive, i.e. greater than about 25, actual degradation of the wound yarn may occur. Furthermore, even a slight break angle is deleterious if variable since it often introduces discernible changes in properties upon the packaged material, particularly with reference to its dye take-up characteristics. A small break angle, i.e. 1 to about 10 is helpful in holding the yarn in the yarn guide. The letter x of the figure designates the radius of the windup body (i.e. the radius of the windup roll or the windup roll and the yarn package thereon).

FIGURE II shows a windup body in three stages of development, i.e., with the windup roll empty 3, with the windup body half full Saand with the full yarn from y to y and to y for windup bodies at 3, 3a, and 3b respectively. A mathematical expression for the path of the center of the winding package may be obtained taking the guide as the origin. This expression is:

where y equals the minimum uncontrolled yarn length, c equals the minimum operable clearance between traverse point and package surface, and x equals the ra dius of the package. This expression confirms the neces sary increase of y as the yarn windup body follows ideal path 7. While ideal path 7 is a rather complicated nonarcuate curvature it can be approximated by a simple arcuate curve 8 having a radius of curvature 9 from a pivot located 'below yarn guide 2 at 10, paths 8 and 7 being tangent at the approximate mid point between the path of travel of the windup body from its initial (3) to its final (3b) position. It will also be obvious that a path can be struck on an arc subtended from a pivot located above yarn guide 9. In this latter embodiment (not shown in the drawing), the arcuate path corresponds to the ideal path at the initial and final positions of the windup body.

From a consideration of FIGURE II it will be seen that any deviation from the ideal path 7 to arcuate path 8 or any other path will result in a variation in the break angle 6 (shown in FIGURE I). The break angle of a yarn windup body following curve 8 will have a minimum break angle at the point of tangency between curves 7 and 8 (i.e. midway between the initial and final positions of the windup body). In this system the break angle will progress from a maximum at the beginning of the windup, pass through a minimum in the middle and return to a maximum at the end of the windup.

' In FIGURE III the windup body is shown in three stages of development, i.e., 3, 3a, and 312, its center of rotation having progressed along arcuate path 8 (related to ideal path 7 as is illustrated in FIGURE II). Since the windup body is surface driven its motion must be followed by drive roll 12. As the windup body moves from its initial position 3 to its final position 3b, drive roll 12 moves from its initial position to its final position (shown in dotted lines) at 12a. The motion of the drive roll 12 can be made to follow the motion of the windup body 3 by pivoting at 13 the motion of the center of rotation of drive roll 12. The center of rotation of drive roll 12 then sweeps out arcuate path 14 having a radius of curvature 15.

F-IGURES IV and V schematically illustrate the apparatus of the present invention, FIGURE IV showing the relation of parts with the windup roll empty whereas FIGURE V shows the same relationship with the windup roll containing a full yarn package 32. In these figures yarn 1 passes through the yarn guide 2 of traverse cam assembly 16, the said assembly being rotatably mounted in machine frame 17. The windup roll assembly comprises bobbin chuck 18 and bobbin 19 rotatably mounted on bobbin'chuck frame 20 which is pivotally mounted by shaft 21 upon machine frame 17. The effective radius of pivoted frame 20 is so designed that the center of rotation of chuck 18 moves along path 8. Drive roll 12 is rotatably mounted upon drive roll frame 22 which in turn is pivotally mounted to machine frame 17 by shaft 23. Frame 22 also carries drive roll motor 24 which rotates drive roll 12 by means of belt 25 which passes over pulleys 26 and 27 mounted upon the shafts of drive roll 12 and motor 24 respectively. The effective radius of pivoted drive roll frame 22 is so designed that the center of rotation of drive roll 12 moves through path 14. A spring 28 anchored on frame 17 maintains contact between drive roll 12 and the windup body assembly. The pivotal motions of drive roll frame 22 and bobbin chuck frame 20 are related through linkage 29 which is rotatably attached to drive roll frame 22 by pin 30 and to bobbin chuck frame 20 by pin 31. The relative motion between the two pivoted frames is a function of age 32, drive roll 12 recedes from the center of the a length a and break angles b and c.

windup body assembly. In its motion of recession through path 14 linkage 29 leads the center of rotation of the windup body through its arcuate path 8. At this point automatic conventional warning or doffing mechanisms (not shown) are activated and an empty bobbin is placed upon the chuck in place of the removed yarn package.

FIGURE VI presents a series of curves for a typical package preparation on an apparatus of the present invention. In this curve package diameter is plotted as abscissa against the separate ordinates uncontrolled yarn Preferably the deviation of break angle is less than about 5". Curve b represents the deviation of the break angle when path 8 is followed, while curve c represents the deviation of break angle when the previously suggested alternate path 11 is followed (FIGURE II). Table I shows the calculated deviations from ideal of the break angle, the clearance from root of guide to surface of package, and the uncontrolled yarn length for a typical yarn package produced on equipment operating according to the instant invention. The clearance increase was specifically selected to allow for possible package surface variations during growth. The values in the table are considered to be those that will give a commercially acceptable product.

Table I Uncon- Package Clearance trolled Break Radius (c), in. Yarn Angle (b), (I), in. Length Deg.

Doffing devices, latches to hold the package in the dofi' position, and dotf-actuated brakes may be employed. Frame 17 is secured to the spinning or processing machine by appropriate means not shown. The unit may be arranged with the rotating axes either parallel or perpendicular to the machine face with the latter arrangement preferred in that it permits the production of dimensionally long packages without direct dependence on machine gage, i.e. the center-to-center distance between adjacent positions.

Many equivalent modifications will be apparent to those skilled in the art from a reading of the above without a departure from the inventive concept.

What is claimed is:

1. A winding machine comprising a windup roll adapted to receive a yarn package rotatably mounted upon a pivoted frame, yarn guide means having a fixed reciprocating path parallel to the longitudinal axis of the said windup roll, the said yarn guide means being positioned to provide a substantially constant minimum operable clearance between the said yarn guide means and the surface of the windup body, the effective radius of the pivoted frame of the said windup body being such that as the yarn package increases, rotation of the said frame on its pivotal axis moves the center of rotation of the said windup roll through a shallow arc of travel which maintains (a) the said substantially constant minimum operable clearance, (b) a minimum variation in the extent of intrusion of the said yarn package beyond the zero break angle line and (c). an intrusion of the said yarn package so that the yarn line from the said yarn guide to the nearest windup contact point on the said windup body produces an angle of less than 25 with the said zero break angle (line, a drive roll for rotating the windup body by surface contact with the yarn wound thereon, a second pivoted frame for supporting the said drive roll to adapt it to recede from the said windup body as the said yarn bundle grows, the efieetive radius of the pivoted frame of the said drive roll being such that rotation of the said frame on its pivotal axis moves the center of rotation of the said drive roll through a shallow are which provides surface contact between the said drive roll and the surface of the windup body as the said windup roll moves through its arc of travel, tension means to hold the said drive roll in surface contact with the said yarn upon the said windup body and linking means between the frame of the said windup body and the frame of the said drive roll, the said linking means transmitting to the said windup body the receding motion of said drive roll at a motion ratio wherein the axis of rotation of the said windup body sweeps out the said shallow are provided by its said pivotal axis druing yarn bundle growth.

2. The apparatus of claim 1 wherein the break angle variation in buildup of a yarn package is less than about 5.

3. The apparatus of claim 2 wherein the break angle is maintained within the limits of from about 1 to about 4. The apparatus of claim 1 wherein the drive roll assembly pivots from a point below the yarn guide of the traverse cam assembly.

5. In a winding machine, a rotatable windup roll for supporting a winding yarn package, yarn guide means having a fixed reciprocating path parallel to the surface of the said winding yarn package, the said windup roll being adapted to recede from the said guide means in a path of travel which provides (a) a substantially constant minimum operable clearance between the said yarn guide means and the surface of the windup body, (b) a variation in the extent of intrusion of the said yarn package beyond the zero break angle line and (c) an intrusion of the said yarn package so that the yarn line from the said yarn guide to the nearest windup contact point on the said windup body produces an angle of less than 25 with the said zero break angle line, a drive roll for rotating the windup body by surface contact with the yarn wound thereon, the said drive roll being adapted to recede from the said windup body as the said yarn bundle grows in a path of travel which provides surface contact between the said drive roll and the surface of the windup body as the said windup roll moves through its said path, tension means to hold the said drive roll in surface contact with the said yarn upon the said windup body and linking means between the said windup body.

and the said drive roll which transmits to the said windup body the receding motion of said drive roll at a motion ratio which provides the said path of travel to the said windup body during yarn bundle growth.

References Cited in the file of this patent UNITED STATES PATENTS 5 86,423 Dewhurst July 13, 1897 1,132,076 De Laski Mar. 16, 1915 2,387,949 Siegenthaler Oct. 30, 1945 2,401,725 Elvin June 11, 1946 2,450,187 Day Sept. 28, 1948 2,752,100 Stange June 26, 1956 2,778,578 Kieth Jan. 22, 1957 FOREIGN PATENTS 1,153,537 France Oct. 7, 1957 610 Great Britain Nov. 12, 1903 

